Create A Pulsing Background With CSS Animation

You can create a smoothly pulsing background effect with CSS animations. This can be achieved by defining a set of keyframes that start at one background color, transitions to another color, and then transitions back to the original color.

@keyframes pulse {
  0%, 100% {
    background-color: #f56a3f;
  }
  50% {
    background-color: #9e42b0;
  }
}

At the beginning (0%) and end (100%) we declare the background color to be #f56a3f. Halfway through (50%) it should be #9e42b0. The browser will animate everything in between.

This can then be applied infinitely with a lengthy duration to give it a real smooth feel.

body {
  animation: pulse 20s infinite;
}

Here is a live example.

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